I’m about the same age, and I know what you mean, but at the same time you can find older travelers. It matters a little where you are going. Some countries have more older travelers than others. I wouldn’t let it affect your plans.
Also, you can meet people through Couchsurfing. I do. It takes an effort, but it’s worth it.
Death to the hostels that age discriminate!
Death to the hostels that age discriminate!
Death to the hostels that age discriminate!